370 CYPSELlDiE. 



rainy season, but in India generally is replaced by the allied 

 Cypselus ajfinis. It has been observed in Persia, and is 

 common in Asia Minor and Palestine. It seems not to have 

 been determined from Egypt until Mr. J. H. Gurney, jun. ob- 

 tained a specimen there in 1875, and its asserted appearance 

 in the rest of North-Eastern Africa is questionable, since 

 C. jiallidus, a form long confounded with it, has perhaps 

 been mistaken for it, but otherwise it ranges, so far as 

 may be inferred, over the whole of that continent, even to 

 the Cape of Good Hope, where it is extremely abundant from 

 towards the end of the year till May. It is not known to 

 occur in the Atlantic islands, but in those of the Mediter- 

 ranean, as well as throughout every country of Europe, it is 

 a well-known summer-visitor. 



The bill is black : irides dark brown : the whole plumage, 

 except a small greyish-white patch under the chin, nearly 

 uniform blackish-brown, glossy above : toes and claws black. 

 There is no external difference between the sexes. 



The whole length is nearly seven inches and a half. From 

 the carpal joint to the tip of the wing, which reaches an inch 

 and a quarter beyond that of the tail, six inches and five- 

 eighths. 



Young birds have the chin of a purer white, and most of 

 the feathers on the upper surface tipped with buflfy-white. 



The middle figure of the vignette represents the sternal 

 apparatus of the Swift, which will be seen at a glance to 

 diff'er most essentially from that of any Passerine bird, in 

 the form of the coracoids and furcula, and in the absence of 

 the forked manubrium or anterior process of the keel, as 

 well as in the absence of the posterior notches of the sternum. 

 The peculiar structure of the foot is also exhibited by the 

 two lateral figures, one shewing that limb with the four toes 

 directed forwards in their ordinary position, and the other 

 the several bones composing it divested of their integu- 

 ments. It will be observed in this figure that the digital 

 phalanges instead of following the usual arithmetical series 

 among birds generally — 2, 3, 4, 5, are 2, 3, 3, 3 — one 

 phalanx being absent in the third digit and two phalanges 



